Big Longnose Butterflyfish (Forcipiger longirostris)

The Big Longnose Butterflyfish (Forcipiger longirostris) known to tropical fish keeping enthusiasts as the Longnose Butterflyfish, is found throughout tropical Indo Pacific waters.

Its range extends from East Africa to the Hawaiian, Marquesan, and Pitcairn islands, north to the Bonin Islands, south to New Caledonia and the Austral Islands; throughout Micronesia.

Big Longnose Butterflyfish are an uncommon benthopelagic species that are normally encountered in pairs along the deeper seaward reefs of their range at depths from 190 feet to over 650 feet where they feed on small whole crustaceans, the tube feet of echinoderms and sea urchins, and polychaete tentacles.

Big Longnose Butterflyfish (Forcipiger longirostris)

Big Longnose Butterflyfish have a laterally compressed, bright yellow body that extends from the back of the head to the caudal peduncle, and a very long thin, silvery snout. There is a black triangular area on the top half of the head that extends all the way through the eye; and the bottom half on the breast is a dusky silvery white color with rows of small black spots. The dorsal and anal fins are predominantly yellow with transparent edges and the pectoral and caudal fins are transparent. They have a black eye spot on the anal fin located just below the caudal peduncle.

The Big Longnose Butterflyfish (Forcipiger longirostris) is easily misidentified as the Yellow Longnose Butterflyfish (Forcipiger flavissimus).   Except for the longer nose, the black cluster of dots on the chest, and the black head color extending to cover the entire eye of Forcipiger longirostris, they are practically identical.

There is a rare all black form of Forcipiger longirostris, and another uncommon form where the yellow portion is

Big Longnose Butterflyfish (Forcipiger longirostris)

dark brown in color.

In the East Indian region of its range, Forcipiger longirostris is replaced by a newly discovered species Forcipiger wanai; which was discovered at Cenderawasih Bay in West Papua.

Forcipiger wanai has the same general shape and coloration as Forcipiger flavissimus and Forcipiger longirostris. However, whereas the first two members of the Forcipiger genus are solid yellow with differences in snout length; Forcipiger wanai is a dusky brownish yellow color that fades to yellow or orange near the fins, with a bright yellow band behind the black head marking.

Big Longnose Butterflyfish are active swimmers that make a wonderful addition to a well established reef or FOWLR aquarium of at least 125 gallon capacity with a sand or fine gravel substrate, plenty of mature live rock arranged into caves, crevices, and overhangs for them to hide and graze among, and lots of free swimming space.

Although the Big Longnose Butterflyfish is a peaceful species that gets along well with other peaceful species, they are very territorial with conspecifics, other butterflyfish species, and similar looking fishes and are best housed singly or as a true mated pair.

Forcipiger longirostris requires excellent water quality and areas in the tank with brisk water movement which makes a good filtration system, protein skimmer, and wave maker mandatory for their well being.

This species benefits tremendously from an ongoing supply of tiny amphipods and copepods which can be easily cultured in a fishless refugium attached to the system.

Forcipiger longirostris has not been bred in a home aquarium environment.

Like the Margined Butterfly (Chelmon marginalis),  Big Longnose Butterflyfish form distinct pairs that mate for life.   During breeding the female deposits small, buoyant eggs into the water column where the male immediately fertilizes them. The buoyant eggs become part of the plankton chain and hatch out into small tholichthys larvae that have large bony plates extending from the head for protection. As the larvae mature and lose their bony plates, the young pass through a lengthy planktonic stage before becoming fully developed juveniles.

Big Longnose Butterflyfish are diurnal omnivores that in their natural habitat feed on Zooplankton, small crustaceans, the tube feet of echinoderms and sea urchins, and polychaete tentacles.

They have tiny mouths that can present challenges when feeding them in an aquarium environment.   A wide variety of fresh or frozen very finely chopped clams, crab, mussels, shrimp, squid, Mysis shrimp, vitamin enriched brine shrimp, etc. fed in small amounts several times per day will keep them healthy.

Many tropical fish keeping enthusiasts set up fishless refugium to culture a continuous supply of small, live amphipods and copepods to keep them in prime condition.

Because of the depths that they are collected from,  Big Longnose Butterflyfish (Forcipiger longirostris) are an uncommon species that are rarely available to tropical fish keeping enthusiasts.   They are occasionally available online from waiting lists from select suppliers and specialty fish shops at prices that vary according to size and area of collection.

Big Longnose Butterflyfish (Forcipiger longirostris)

Minimum Tank Size: 125 gallons
Aquarium Type: FOLR or Reef
Care Level: Moderate
Temperament: Peaceful
Aquarium Hardiness: Moderately Hardy
Water Conditions: 72° – 78° F, dKH 8 – 12°, pH 8.1 – 8.4, sg 1.020-1.025
Max size: 8.7″
Color Form: White, Black, Orange, Yellow
Diet: Omnivore
Compatibility: Excellent Reef species
Origin: Indo Pacific
Family: Chaetodontidae
Lifespan: 5-10 years
Aquarist Experience Level: Intermediate